1. Field of the Invention
The invention relates to the delivery of therapy to a subject to treat respiratory disorders in which average tidal volume, respiratory rate, and/or positive end expiratory pressure are controlled automatically.
2. Description of the Related Art
Obesity Hypoventilation Syndrome is a respiratory syndrome where obese subjects (e.g., subjects with >30 kg/m2 Body Mass Index) suffer from hypoxia and hypercapnia resulting from shallow or insufficient respiration. Other syndromes and/or conditions have these and/or other symptoms. Systems configured to deliver pressurized gas to the airway of such subjects to facilitate respiration are known. Such systems include systems that are configured to maintain a therapeutic respiratory rate and an average tidal volume per breath.
In conventional systems, the therapeutic respiratory rate may be a setting that is configured by a user (e.g., a subject, a caregiver, a therapy decision-maker, a researcher, and/or other users). In such systems, the therapeutic respiratory rate may not take into account measurements of spontaneous respiration by a subject.
Typically, in systems that maintain an average tidal volume, every breath is supported at the same pressure levels. These systems generally are not configured to support spontaneous and non-spontaneous breaths at different pressure levels.